An Application of Pulse Frequency Modulation Photosensors to Sub- retinal Artificial Retina Implantation
نویسندگان
چکیده
In this paper we discuss an application of CMOS photo-sensor array chip using pulse frequency modulation (PFM) to sub-retinal implantation to recover human vision. PFM with integration mode as photo-sensing circuit is used to realize enough dynamic range and compatibility with signals in real retina. To effectively stimulate the retinal cells, we have designed a PFM circuit with limited bandwidth of output pulses and two kinds of pulse shaping circuits with digital waveform memory and pixel-level output amplitude tuner. We have fabricated a PFM photo-sensing test circuits with a standard 0.35 μm CMOS technology to measure its basic characteristics, and have demonstrated a large dynamic range of around 40 dB.
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